Drill



' c. H. GARDNER, JYR

DRILL Filed Jan. 22, 1938 April 9, 1940.

2 Sheets-Sheet l fly-1 1 INVENTOR ATTORNEYS WITNESS Patented Apr. 9, 1940 UNITED STATES PATENT OFF! mun. I Charles 11. Gardner, In, Pleasant Grove, Calif. Application January 22, 1938, Serial No. 188,475

3 Claims. (01. 71-32) This invention relates to drills and has for the primary object the provision of .a portable power driven device provided with hydraulic means for placing force on the drill bit as it is advanced towards the work relieving the operator of the manual efi'ort necessary in the advancement of the bit in the work and which may be conveniently rendered operative and inoperative as desired.

With these and other objects in view, this inventionconsists in certain novel features of construction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of my invention,

reference is to be had to the following description and accompanying drawings, in which Figure 1 is a fragmentary side elevation, partly in section, showing a. hydraulic device constructed in accordance with my invention and adapted to a fragmentary portion of a power driven drill.

Figure 2 is a detail sectional view illustrating a control valve for the hydraulic device.

Figiu-e 3 is a vertical sectional view illustrating a modified form of my invention.

Referring in detail to the drawings, the numeral i indicates a fragmentary portion of a power driven portable hand drill including the 30 hand grips 2 for the manipulation of the drill.

To eliminate the necessity of the operator of the drill having to support and advance the drill as it bores my invention is mounted on the drill l and consists of a cylinder 3 in which operates a piston 4 dividing the cylinder into chambers 5 and 6. The stem of the piston 4 is indicated by. the character 'I and extends through a stufllng gland 8 of the cylinder 3 and has secured thereto a rest or head 9 which may be 40 brought into contact with a permanent object (not shown) while the bit of the drill (not shown) is in engagement with the work. Liquid is placed in the chambers 5 and 6 and connected thereto are pipes ill and II. Connected to the 1 45 pipes 10 and II is ahead actuated pump I2 of the plunger type mounted on one of the hand grips'2 of the drill. Check valves ii are located in the pipes Ill and II and are oppositely arranged so that the pipe III will provide the in- 50 let to the pump while the pipe ll provides the outlet for said pump. A suitable control valve I4 is connected with the pipes l0 and II for closing said pipes to the pump and for bringing said pipes in direct communication with each 56 other, as shown bydotted lines in l lsure 2, when chambers 2| and 22 formed it is desired to permit free circulation of the liq- 'uid farom one chamber to the other of the cylinder In operation, the rest 9 is placed against a fixed support oppositr to the work which the bit 5 of the drill engages and with the drill bit operating the operator actuates the pump i2 drawing liquid out of the chamber 5 and forcing said liquid into the chamber 6. The liquid entering the chamber 8 acts on the piston 4 and creates l0 apressure on the drill bit to advance the same towards or into the work-as the drill bit cuts.

Whenever it is desired to return the liquid from the chamber, 8 to the chamber 5 the valve I4 is operated to place the pipes I 0 and II in 15 direct communication, the piston 4 may then be easily moved manually bringing about the transfer of the liquid from the chamber 6 to the chamber 5. y

Referring to the modified form of my inven- 20 tion, the drill is indicated by the character l5 and is of the electrical motor driven type, the motor being indicated by the character I6 and connected to the bit chuck ll by gearing I8. The operating handles for the drill are indicated by the character i 9. The motor casing includes in its construction a cylinder 20 including by the piston 23. The stem of the piston is indicated by the character 2| and has a rest or head 25. Located in the motor casing is a rotary type gear pump 26, the intake port of which is connected to the chamber 2| by a pipe 21 and the outlet port is connected to the chamber 22 by a pipe 28. One of the shafts of the gearing I8 is indicated by the character 20 and is connected to one of the gears of the pump so that when the electric motor is in operation the pump also will be operated acting 'to draw liquid from the chamber 2| and force said liquid into the chamber 22 for the 40 advancement of the drill bit in the work with the rest 25 against a fixed object. To control the advancement of the drill bit with the electric motor in operation, a bypass pipe 3| is connected to the pipes 21 and 28 and is controlled by a manually actuated valve 32 mounted on one of the hand grips l9. Whenever it is desired to stop the advancement of the drill bit in the work or the transfer of the liquid from the chamber 2| to the chamber 22 of the pump the valve 32 is manually opened, permitting the liquid actuated or forced by the pump to be bypassed and not forced into the chamber 22.

What is claimed is:

1. In combination with a powerdriven drill having a drillblt driven by an electric motor, a cylinder carried by said drill, a piston in said cylinder and providing separable fluid chambers in the cylinder, a. stem on the piston, a rest carried by the stem to engage a flxed object, a gear pump carried by the drill and driven by the electric motor, pipes connecting the ports oi the pump to said chambers whereby the operation or the pump will displace fluid from one chamber into the other chamber, and a manually controlled bypass means connecting said pipes for the stopping of the displacement of the fluid from said chamber to the other chamber by said pump.

2. In combination with a drill having an elec- 15 tric motor for driving the same, a drill pressure means, a liquid circuit for operating the pressure means to apply pressure to the drill, a pump in said liquid circuit, and an operating connection between the motor and said pump for placing the liquid under pressure to apply drilling pressure to the drill. I

3. In combination with a drill having an electric motor for driving the same, a drill pressure means, a liquid circuit for operating the pressure means to apply pressure to the drill, a pump in said liquid circuit, an operating connection between the motor and said pump for placing the liquid under pressure to apply drilling pressure to the drill, and a manually controlled valve for by-passing liquid. H. GARDNER, Jr. 

